Benign prostatic hyperplasia is a non-cancerous enlargement of the prostate gland, affecting more than 50% percent of men over the age of 60. The prostate early in life is the size and shape of a walnut and weight about 20 grams. Prostate enlargement appears to be a normal process. With age, the prostate gradually increases in size to twice or more its normal size. As the prostate grows, it presses against and narrows the urethra, causing a urinary obstruction that makes it difficult to urinate.
Male urethral stricture disease occurred at a rate as high as 0.6% in some populations. Urethral stricture diseases appeared to be more common in the elderly population. The patients with the strictures experience moderate complications, such as bother from lower urinary tract voiding symptoms, recurrent urinary tract infection and the need for repeat urethral procedures such as dilation or urethrotomy.
Ureteral strictures of upper urinary tract are either congenital or acquired. Congenital ureteral strictures are most commonly located at the ureteropelvic junction. Most of ureteral strictures are acquired and usually are iatrogenic. The most common etiology of the ureteral strictures is injury during endoscopic, open, or laparoscopic surgical procedures.
Esophageal strictures are a problem commonly encountered in gastroenterological medicine and can be caused by malignant or benign lesions. Dysphagia is the symptom experienced by all patients. Most of these patients require palliative treatment to relieve the dysphagia.
Chronic obstructive pulmonary disease (COPD) is a term used to classify two major airflow obstruction disorders: chronic bronchitis and emphysema. Approximately 16 million Americans have COPD, 80-90% of them were smokers throughout much of their lives. COPD is a leading cause of death in the U.S. Chronic bronchitis is inflammation of the bronchial airways. The bronchial airways connect the trachea with the lungs. When inflamed, the bronchial tubes secrete mucus, causing a chronic cough. Emphysema is an overinflation of the alveoli, or air sacs in the lungs. This condition causes shortness of breath.
Asthma is a chronic respiratory disease characterized by inflammation of the airways, excess mucus production and airway hyper responsiveness, and a condition in which airways narrow excessively or too easily respond to a stimulus. Asthma episodes or attacks cause narrowing of the airways, which make breathing difficult. Asthma attacks can have a significant impact on a patient's life, limiting participation in many activities. In severe cases, asthma attacks can be life threatening. Presently, there is no known cure for asthma.
Chronic sinusitis is an inflammation of the membrane lining of one or more paranasal sinuses. Chronic sinusitis lasts longer than three weeks and often continues for months. In cases of chronic sinusitis, there is usually tissue damage. According to the Center for Disease Control (CDC), thirty seven million cases of chronic sinusitis are reported annually.
One of the most common treatments of the strictures described above is balloon catheter dilation. The balloon dilation usually results in symptomatic relief, however, the effect may not persist and recurrent strictures do occur. Repeated the balloon dilations or surgical procedures are often used to treat the recurrent strictures.
The causes of coronary heart disease and the strictures are neointimal proliferation of smooth muscle in arterial vessels and in walls of body lumen. One aspect of the invention is to deliver paclitaxel or rapamycin and their analogues to the wall of body lumen to treat the narrowing and strictures. Drug coated stents and drug coated balloon catheters with these drugs have been approved for inhibiting the growth of the smooth muscle cells in vascular arterial vessels.
The present invention provides new methods for treatments of nonvascular diseases of benign prostatic hyperplasia (BPH) strictures, urethral strictures, ureteral strictures, prostate cancer, esophageal strictures, biliary tract strictures, asthma and chronic obstructive pulmonary disease (COPD) to have a long term persist effect. The new methods will prevent renarrowing and recurrent strictures in years. The methods involve delivering of anti-inflammatory and anti-proliferate drugs (rapamycin or paclitaxel and their analogues) and an additive to a target tissue. Embodiments of the present invention provide a medical device coating formulation comprising a drug for treatment of the nonvascular strictures, and an additive that enhances absorption of the drug into tissue of body lumens.